The present invention concerns a system for ascertaining a fluid level in a receptacle and, in particular, to an ink cartridge for an inkjet printer and an associated receptacle.
Such a system and/or an associated receptacle is described in EP 0 860 284 A2. The known fluid level recognition system serves for detection of whether or not fluid or ink is present in the receptacle chamber of an ink receptacle or an ink cartridge. Into the receptacle wall of the known receptacle is integrated a fixed and transparent deviating prism, which projects into the chamber. The deviating prism is irradiated by a light source outside the receptacle, and redirects the light to an external photo detector when the receptacle is empty. If the receptacle is filled, the beam of light enters through the deviating prism into the liquid and is there randomly diffused. No light is returned back to the photo detector. The known system is thus essentially only capable of recognizing the state of emptiness of the receptacle.
It is desired to provide a system for determining a fluid level in a receptacle and an associated receptacle, by means of which it is possible to register several fluid level stages.
A system is provided for ascertaining a fluid level of a fluid in a fluid chamber of a receptacle, in particular of ink in an ink cartridge, including a light source, which shines into the chamber of the receptacle, a reflection body or a reflector, which is designed as floating body, which moves about in the chamber of the receptacle, dependent upon the fill level of the fluid and which variably reflects the light dependent upon its movement or attained position or location, and a light detector or photo detector, which, dependent upon the movement of the reflection body, receives variable amounts of light.
As a result of the movement of the reflector in dependency upon the level of fluid in the receptacle chamber, the system according to the invention facilitates the detection of different fluid levels or several level stages or also continuous level registration.
The reflection body can have several identically or differently shaped recesses on its surface so that, depending upon movement, different fill level phases can be registered.
The reflection body, in essence, is preferably a cylinder, in which extends at least one cylindrical hollow space parallel to a central axis of the cylinder and extending continuously between the end surfaces of the cylinder. With such construction it is possible to achieve a level-dependent rotation of the reflector around its axis and a correspondingly variable reflection and thereby detection of light.
A guiding mechanism is selectively provided which guides the reflection body in its movement with the level of fluid in the fluid chamber of the receptacle. The guiding mechanism facilitates a straight-line level-dependent movement of the reflection body over a specified distance.
The reflection body may be a float unit which is arranged, by means of a flexible or rigid suspension, at a lid or a wall of the receptacle.
The reflection body can have a recess on its surface, whose walls or surfaces deviate the light beam from the source of light and which thus acts as deviation level or deviation reflector.
The reflection body can be a float unit in form of a transparent prism or deviation prism, which moves along with the fluid level inside the receptacle.
The present invention, moreover, relates to a receptacle, in particular for ink of an inkjet printer, having a receptacle wall, which encloses a fillable and evacuatable fluid chamber of the receptacle, and with a reflection body which is designed as float unit, which moves in the fluid chamber of the receptacle in dependency upon the fill level and which variably reflects linked-up light in dependency upon its movement or attained position or location within the fluid chamber.
Additional application possibilities of the invention are, for example, the color reservoir of a printing device, the water tank of a coffee machine, a water boiler, etc., a gasoline tank, a toilet flushing tank or, for example an air humidifier or a water level indicator in the field of hydro-culture.
Additional benefits, beneficial modifications or application possibilities of the present invention are apparent from the following description of preferred specific embodiments of the invention, together with the drawings.